825 research outputs found

    VUV-Vis optical characterization of Tetraphenyl-butadiene films on glass and specular reflector substrates from room to liquid Argon temperature

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    The use of efficient wavelength-shifters from the vacuum-ultraviolet to the photosensor's range of sensitivity is a key feature in detectors for Dark Matter search and neutrino physics based on liquid argon scintillation detection. Thin film of Tetraphenyl-butadiene (TPB) deposited onto the surface delimiting the active volume of the detector and/or onto the photosensor optical window is the most common solution in current and planned experiments. Detector design and response can be evaluated and correctly simulated only when the properties of the optical system in use (TPB film + substrate) are fully understood. Characterization of the optical system requires specific, sometimes sophisticated optical methodologies. In this paper the main features of TPB coatings on different, commonly used substrates is reported, as a result of two independent campaigns of measurements at the specialized optical metrology labs of ENEA and University of Tor Vergata. Measured features include TPB emission spectra with lineshape and relative intensity variation recorded as a function of the film thickness and for the first time down to LAr temperature, as well as optical reflectance and transmittance spectra of the TPB coated substrates in the wavelength range of the TPB emission

    A Chronology of the Introduction of Domesticated Plants in Central Brazil

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    The paleoethnobotanical analysis of archaeological remains from two sites in central Brazil provides chronological data for the introduction of domesticated plants to the region. The sites of Lapa dos Bichos and Lapa Pintada, located in the northern portion of the state of Minas Gerais, are within rock shelters in limestone rock outcroppings. The dry conditions at the sites preserved both burnt and unburnt organic materials, including the seeds and fruits that were analyzed in this study. The chronological documentation for the introduction of domesticated plants is based on relative chronology from excavation stratigraphy and radiocarbon dating. The domesticated plants found include maize (Zea mays), manioc (cf. Manihot esculenta), cotton (cf. Gossypium barbadense), peanut (Arachis hypogaea), common bean (Phaseolus vulgaris), bottle gourd (Lagenaria siceraria), and squash (Cucurbita spp.). Central Brazil is not documented as the region of origin for these species and as such is a periphery where they were introduced. Maize and manioc are found in the strata dated between 750 and 2000 BP at Lapa dos Bichos and c. 1200 BP at Lapa Pintada; bottle gourd occurs in earlier strata (2000 to 4250 BP at Lapa dos Bichos). In addition to domesticated plants, numerous native plant foods were identified in the archaeological assemblage, such as palm nuts (Syagrus oleracea), passion fruit (Passiflora spp.), jatobĂĄ (Hymenaea spp.), umbu (Spondias tuberosa), and pequi (Caryocar brasiliensis). At the site of Lapa dos Bichos human habitation is known to span the entirety of the Holocene. Based on the archaeological macroscopic plant remains, the introduction of domesticated plants to central Brazil was a gradual process

    Porcine circovirus 3 is highly prevalent in serum and tissues and may persistently infect wild boar (Sus scrofa scrofa)

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    Porcine circovirus 3 (PCV‐3) prevalence has been minimally investigated in wild boar; dynamics of infection and viral tissue distribution are currently unknown. In this study, serum samples from 518 wild boar (from years 2004 to 2018) were used to study frequency of infection. Also, serum samples from 19 boar captured and recaptured at least two times for a period of time from 1 month to 1 year were collected to determine PCV‐3 infection dynamics. Finally, to elucidate PCV‐3 DNA organic distribution, sera, different tissues and faeces were obtained from 35 additional wild boar. PCV‐3 DNA was extracted and amplified with a conventional PCR. For the PCV‐3 PCR‐positive sera from the longitudinally sampled and different tissue types, a quantitative PCR was performed. Genome sequence was obtained from a number of PCV‐3 PCR‐positive samples from different years, different time‐points of infection and tissues. Obtained results confirmed the susceptibility of wild boar to the virus, showing high frequency of PCV‐3 detection (221 out of 518, 42.66%) and demonstrating circulation at least since 2004. Compiled data indicate the possibility of long‐term infections, since 5 out of 10 PCV‐3 PCR‐positive boars longitudinally sampled showed positivity in samplings separated for more than 5 months. All tested tissue types' harboured PCV‐3 genome, with the highest percentage of PCR positivity in submandibular lymph node, tonsil, lung, liver, spleen and kidney. The amount of DNA in all tested PCV‐3 PCR‐positive samples was moderate to low. All partial and complete PCV‐3 sequences obtained from wild boar displayed high nucleotide identity, higher than 98%. In conclusion, this study further confirms that wild boar is susceptible to PCV‐3 infection, showing high frequency of detection in this animal species. Furthermore, PCV‐3 can be found in different tissues of wild boar and is apparently able to cause persistent infection.Instituto Nacional de Investigación y Tecnologia Agraria y Alimentaria. Grant Number: E‐RTA2017‐00007‐00‐0

    Cocoa Bar Antioxidant Profile Enrichment with Underutilized Apples Varieties

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    : The impact of dried apples (Malus × domestica Borkh.) addition on improving the antioxidant characteristics of dark chocolate was evaluated. The antioxidant activity was measured through DPPH scavenging activity and showed an increase in the cocoa bar with 'Nesta' dry apple (17.3% vs. 46.8%) in comparison to cocoa mass. The 15 polyphenols analyzed by UHPLC-ESI-MS/MS indicated great variability among the apple varieties. Quercetin was detected in the highest concentrations (ranged from 753.3 to 1915.5 ”g g-1), while the lowest were for kaempferol 7-O-glucoside, measured only in 'Mora' and 'Nesta' cocoa bars (from 0.034 to 0.069 ”g g-1, respectively). P-coumaric acid, trans-ferulic acid, and chlorogenic acid contribute largely to the antioxidant activity in cocoa bars. Principal component analysis shows that a cocoa bar with the addition of 'Nesta' dry apple differ from others due to its higher content of polyphenols (1614 ± 61.8 mg gallic acid equivalents per 100 g). In conclusion, data confirm that cocoa bars with dry apples might be considered as a polyphenol-enriched food

    The new hyperspectral satellite prisma: Imagery for forest types discrimination

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    Different forest types based on different tree species composition may have similar spectral signatures if observed with traditional multispectral satellite sensors. Hyperspectral imagery, with a more continuous representation of their spectral behavior may instead be used for their classification. The new hyperspectral Precursore IperSpettrale della Missione Applicativa (PRISMA) sensor, developed by the Italian Space Agency, is able to capture images in a continuum of 240 spectral bands ranging between 400 and 2500 nm, with a spectral resolution smaller than 12 nm. The new sensor can be employed for a large number of remote sensing applications, including forest types discrimination. In this study, we compared the capabilities of the new PRISMA sensor against the well-known Sentinel-2 Multi-Spectral Instrument (MSI) in recognition of different forest types through a pairwise separability analysis carried out in two study areas in Italy, using two different nomenclature systems and four separability metrics. The PRISMA hyperspectral sensor, compared to Sentinel-2 MSI, allowed for a better discrimination in all forest types, increasing the performance when the complexity of the nomenclature system also increased. PRISMA achieved an average improvement of 40% for the discrimination between two forest categories (coniferous vs. broadleaves) and of 102% in the discrimination between five forest types based on main tree species groups
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